David Suchet has spent the past 25 years playing Hercule Poirot in ITV's adaptations of Agatha Christie's Belgian detective stories, breaking off only to star in carefully-chosen dramas, tours and theatre productions to keep him challenged. But in the past year, as he has recorded the final episodes of the 70-part Poirot series while also starring in Eugene O'Neill's A Long Day's Journey Into Night, the 67-year-old actor has pursued a passion project. He has spent 200 hours recording the entire Bible from Genesis to the Book of Revelation – 752,702 words, in his deep, melodic, unrushed voice. Publisher Hodder Stoughton says it is the first time a single British actor of stature has tackled it. The recording is now in the editing stages, for a 78-hour release next Easter.

The extent of Suchet's commitment surfaced when In the Footsteps of St Paul, a two-part documentary he made for BBC1, won the premier prizes at the Sandford St Martin's Trust religious programme awards in June . To accompany those Christmas programmes, for which Suchet toured the eastern Mediterranean, he recorded The Acts and Letters of St Paul, which were released without fanfare by Hodder. A further instalment of The Gospels followed at Easter. But the executive producer of the St Paul programmes, Ray Bruce, struck fertile ground when he suggested that Suchet record the entire Bible with him. The studio was just south of Tower Bridge, opposite Suchet's home on the Thames. "He always arrived prepared, for three-hour sessions … And then he went on to perform on stage. It was the most remarkable thing I have ever done in 40 years," said Bruce.

He is clear it was about "David Suchet's personal journey". The background is that St Paul is very close to the actor's heart because he was converted to Christianity when reading a Bible in a hotel room in 1986. Suchet's moment of epiphany came with St Paul's epistle to the Romans, chapter eight, in which the evangelist lays out the Christian hope of salvation – ( "if God be for us, who can be against us?"). He was subsequently confirmed and has said : "I am a Christian by faith. I like to think it sees me through a great deal of my life."

On winning the Sandford St Martin's Trust award, he said in a prepared response: "If there was ever an historical character I would like to play it is St Paul. So for me this is a very personal prize … He is the man more than anyone who turned a small Jewish sect into the world faith it is today, his words echo down history … Two thousand years ago, he travelled 10,000 miles around the Roman world by foot and many more by sea, he was hugely controversial and still is today".

In 1989 Suchet was one of a band of leading British actors who recorded different parts of the Bible for an earlier Hodder project: he read the Gospel of St John. But the master tape was lost in an office move, according to Hodder Faith director Ian Metcalfe. Suchet subsequently got in touch with him after a woman wrote to him, saying she had been losing her sight, and had been given an old cassette tape of his recording. It had transformed her life, Metcalfe said, adding that Suchet raised the prospect of recording the Bible.

The publication in 2011 of the latest New International Version of the Bible, overseen by more than 100 scholars, cleared the way for the recording. Hodder is the rights holder in the UK for the Biblica consortium who back the NIV project. Metcalfe said: "I am delighted the whole thing came together. It is amazing, just having David Suchet is transformatory. The fact is that people love him for other things, for Poirot, so there is a wonderful opportunity for them to find this (too). It is a labour of love, and so much of a benefit to everyone".

Poirothas been shown in more than 100 countries, and it is estimated that between 600-700 million have watched Suchet's portrayal.

The Bible recording will be an "enhanced" ebook and will offer readers/listeners the choice of picking out a chapter andlistening at the same time. In true Christian spirit, he is donating the fee for his 200 hours of work to charity.